[PATCH] mm: remove lru_add_drain_all in alloc_contig_range

From: Minchan Kim
Date: Tue Feb 09 2021 - 14:03:27 EST


__alloc_contig_migrate_range already has lru_add_drain_all call
via migrate_prep. It's necessary to move LRU taget pages into
LRU list to be able to isolated. However, lru_add_drain_all call
after __alloc_contig_migrate_range is called is pointless.

This patch removes it.

Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
---
mm/page_alloc.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6446778cbc6b..f8fbee73dd6d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8603,8 +8603,6 @@ int alloc_contig_range(unsigned long start, unsigned long end,
* isolated thus they won't get removed from buddy.
*/

- lru_add_drain_all();
-
order = 0;
outer_start = start;
while (!PageBuddy(pfn_to_page(outer_start))) {
--
2.30.0.478.g8a0d178c01-goog